DD263779B5

DD263779B5 - Process for the preparation of homo- or copolymers of vinyl chloride

Info

Publication number: DD263779B5
Application number: DD25325083A
Authority: DD
Inventors: Volker Dipl-Chem Dr Kiesel; Malte-Christoph Kindelberger; Gudrun Kuhn; Harald Dipl-Chem Schirge; Bernhard Dipl-Ing Tippelt
Original assignee: Buna Ag
Priority date: 1983-07-21
Filing date: 1983-07-21
Publication date: 1994-05-26
Also published as: DD263779A1

Description

Example 2

Analog Beispiel 1 wird der 100-l-Druckkessel mit 120 Teilen Wasser und 1,5 Teilen Alkylsulfonat chargiert. Nach dem Spülen mit Stickstoff werden zeitgleich die VC-Dosierpumpe mit 50 l/h und die Initiatordosierpumpe mit 120 ml/h zugeschaltet. Es wird eine 40%ige Initiatordispersion, bestehend aus 0,01 Teilen Dilauroylperoxid und 0,03 Teilen Dicetylperoxidicarbonat, dispergiert mit Celluloseäther in Wasser, verwendet, die über eine Kapillarleitung mit Düseneinsatz unmittelbar hinter der VC-Dosierpumpe in den Monomerstrom gesprüht wird, der nach 100 Teilen abgestellt wird. Das gesamte Ansatzgemisch wird anschließend wie in Beispiel 1 dispergiert und homogenisiert, bei 52⁰C polymerisiert, nach 8 Stunden bei einer Gelphasentemperaturerhöhung auf 62⁰C entspannt und sprühgetrocknet. Das Produkt ist charakterisiert durch folgende Kennwerte:Analogously to Example 1, the 100 liter pressure vessel is charged with 120 parts of water and 1.5 parts of alkyl sulfonate. After purging with nitrogen, the VC dosing pump with 50 l / h and the initiator dosing pump with 120 ml / h are switched on at the same time. It is a 40% initiator dispersion consisting of 0.01 parts of dilauroyl peroxide and 0.03 parts of dicetyl peroxydicarbonate, dispersed with cellulose ether in water, used, which is sprayed via a capillary line with nozzle insert immediately behind the VC metering pump in the monomer stream after 100 parts is turned off. The entire batch mixture is then dispersed and homogenized as in Example 1, polymerized at 52 ⁰ C, relaxed after 8 hours at a gel phase temperature increase to 62 ⁰ C and spray-dried. The product is characterized by the following characteristics:

M_w:M_n 2,3M _w : M _n 2,3

Particle size distribution from 80 to 2000 nm Paste PVC: DOP = 3: 2 at D = 48.6s ~ ¹ with a viscosity of 2500mPas Example 3

Die Durchführung erfolgt analog Beispiel 2, nur wird anstelle der Initiatordispersion eine 10%ige Lösung beider Initiatoren zu Anteilen analog Beispiel 2 in Xylol verwendet, die mit einer Dosierpumpeneinstellung von 500ml/h in den Monomerstrom eingesprüht wird. Die Polymerisation ist nach 8 Stunden mit einer Gelphasentemperaturerhöhung auf 58"C beendet. Das analog Beispiel 2 hergestellte Produkt hat folgende Kenndaten:The procedure is analogous to Example 2, except that instead of the initiator dispersion, a 10% solution of both initiators to proportions used as in Example 2 in xylene, which is sprayed with a Dosierpumpeneinstellung of 500ml / h in the monomer stream. The polymerization is complete after 8 hours with a gel phase temperature increase to 58 ° C. The product prepared analogously to Example 2 has the following characteristics:

M_w:M_n , 2,2M _w : M _n , 2.2

Particle size distribution 100 to 1800 nm PastoPVC: DOP = 3: 2beiD = 48,6s ~ ^l miteinerViskositätvon2200mPas Comparative Example (Example 4)

In einem 100-l-Dr.uckkessel mit Impellerrührer und Stromstörer werden 180 Teile Wasser, 0,1 Teile Propoxymethylcellulose und 0,06 Teile Dilauroylperoxid sowie 0,015 Teile Diisopropylperoxidicarbonat vorgelegt. Nach dem Spülen mit Stickstoff werden 100 Teile VC zudosiert und bei 1 lOUpr.i und 55⁰C polymerisiert. Nach 6 Stunden bei einer Gelphasentemperaturerhöhung auf 70⁰C wird das restliche Monomere entfernt, die Dispersion über Dekanter entwässert und das Produkt im Fließbett getrocknet. Es wird durch folgende Kennwerte charakterisiert:180 parts of water, 0.1 part of propoxymethylcellulose and 0.06 part of dilauroyl peroxide and 0.015 part of diisopropyl peroxydicarbonate are placed in a 100 l pressure-jackpot reactor with impeller stirrer and baffle. After purging with nitrogen, 100 parts of VC are metered in and polymerized at lOUpr.i 1 and 55 ⁰ C. After 6 hours with a gel phase temperature increase to 70 ⁰ C, the residual monomer is removed, the dispersion is drained via decanters and the product is dried in a fluidized bed. It is characterized by the following characteristic values:

M_W:M„ 2,6M _W : M "2.6

Kornanteil <63|im 12% WeichmacheraufnahmeGrain fraction <63 | in 12% plasticizer absorption

(Zentrifugenmethode) 25%(Centrifuge method) 25%

Example 5

In einem 100-l-Druckkessel analog Beispiel 4 werden 180 Teile Wasser und 0,1 Teile Propoxymethylcellulose vorgelegt. Nach dem Spülen mit Stickstoff werden zeitgleich die VC-Dosierpumpe mit 50l/h und die Initiatordosierpumpe mit 500 ml/h zugeschaltet. Es wird eine 10%ige Lösung der anteiligen Initiatormengen analog Beispiel 4 verwendet, die unmittelbar hinter der VC-Dosierpumpe über eine Düse in den Monomerstrom eingesprüht wird. Nach dem Zusatz von 100 Teilen VC wird die Dosierung abgestellt, das gesamte Ansatzgemisch bei 110Upm und 55°C 5 Stunden polymerisiert, wobei eine Gelp'nasentemperaturerhöhung bis 6O⁰C eintritt. Anschließend wird das Produkt analog Beispiel 4 aufgearbeitet und ist durch folgende Kenndaten zu charaiüerisieron:In a 100 liter pressure vessel analogous to Example 4, 180 parts of water and 0.1 parts of propoxymethylcellulose are presented. After purging with nitrogen, the VC dosing pump with 50 l / h and the initiator dosing pump with 500 ml / h are switched on at the same time. A 10% strength solution of the proportionate amounts of initiator analogous to Example 4 is used, which is sprayed into the monomer stream via a nozzle directly behind the VC metering pump. After the addition of 100 parts of VC, the dosage is turned off, the entire batch mixture polymerized at 110 rpm and 55 ° C for 5 hours, with a Gelp'nasentemperaturerhöhung to 6O ⁰ C occurs. The product is then worked up analogously to Example 4 and is charaiüerisieron by the following characteristics:

M_W:M„ 2,2M _W : M "2.2

Kornanteil <63 pm 2% WeichmacheraufnahmeGrain fraction <63 pm 2% plasticizer absorption

(Zentrifugenmethode) 15%(Centrifuge method) 15%

Claims

Process for the preparation of homo- or copolymers of vinyl chloride by the suspension and microsuspension process using known macromolecular dispersants or combinations in amounts of 0.01 to 0.2% by mass and / or known emulsifiers or combinations in amounts of 0.2 to 3% by mass, based in each case on monomer, and of known initiators, characterized in that the initiator or the initiator combinations as aqueous dispersion or as solution in an inert organic solvent via a nozzle with Reynolds numbers before dispersing with water 5000 are uniformly metered to the entire monomer stream leading into the reactor so that residence times of the initiator-monomer mixture of> 10 seconds are set before mixing with water.

The invention relates to a process for the preparation of homo- or copolymers of vinyl chloride by the suspension and microsuspension process using known macromolecular dispersants or combinations in amounts of 0.01 to 0.2 wt .-% and / or known emulsifiers or combinations in amounts from 0.2 to 3 M3 .-%, each based on monomer.

In the known methods of suspension and microsuspension polymerization of vinyl chloride, it is customary to introduce the initiator in batch form with all other starting materials and then carry out the known reactions (Houben-Weyl, Methoden der Organischen Chemie, 1961, Vol. 14/1 p .882). The problem of uniform distribution of the initiator is very incomplete to solve, and there are particles with very different product properties. There has therefore been no lack of attempts to distribute the monomer homogeneously with the initiator. Thus, it is known to dissolve the initiator in a solvent, to divide this to a desired quality corresponding drop size in the water and then bring the monomer by diffusion in the solvent drops (DE-OS 2,737,112). The disadvantage is the relatively large, the reaction process negatively affecting amount of solvent and the complex time-dependent monomer diffusion. Furthermore, processes are known which stir the batch batch vigorously for a long time before the start of the polymerization so as to guide the mass transfer between the monomer droplets for uniform distribution (JP Kokai 79163 983). In addition to the economically unjustifiable loss of time, depending on the substance system, the replacement of the initiators is limited and not complete, in particular emulsifier and dispersant protective layers block the mass transfer between monomer droplets. It is also known either to introduce the entire initiator in a small amount of monomer and to add the remaining monomer onto the polymerizing particles (German Offenlegungsschrift No. 2 427 953) or to polymerize the monomers which are not completely reactive by subsequently added initiators (German Offenlegungsschrift No. 2,039,010). In both cases, it is disadvantageous that the diffusion-dependent process is substance-dependent, run through the blocking auxiliary side reactions in the aqueous phase and thus no homogeneous product of suspension or microsuspension produced.

The use of the technologically and safety-easy-to-handle initiator dispersions for suspension and microsuspension is known in batch approaches (DE-OS 2,634,131), but complicates the initiator transition into the monomer and therefore does not solve the problems of homogeneous distribution.

The use of initiator sluice: n is also known, in which the entire initiator is introduced and the monomer is passed through (DE-OS 2 442 574). However, it is not possible to dissolve over the entire monomer current a constant amount of initiator, so that there is still the problem of uneven distribution.

There is no method known from the prior art, which distributes the initiators in an economical and technologically simple manner in the monomer so that a uniform reaction in all drops results in homogeneous product properties. The object of the invention is to produce monomer-water mixtures with initiator contents which allow a uniform reaction to obtain polymers with improved performance properties. The technical problem which is solved by the invention.

The invention has for its object to develop a process for the preparation of homo- or copolymers of vinyl chloride using conventional technical equipment in which arise by the distribution of the initiator in the monomer, a uniform reaction and a polymer with narrower molecular and particle size distribution. The object is achieved according to the invention by the monomers prior to dispersion with water, the known initiator or the known initiator combinations as aqueous dispersion or as a solution in an inert organic solvent through a nozzle with Reynolds numbers> 5000 evenly throughout the monomer stream leading into the reactor be dosed so that before mixing with water residence times of the initiator monomer mixture of> 10 seconds are set.

Comparative Example (Example 1)

120 parts of water, 1.5 parts of alkylsulfonate, 0.1 part of dilauroyl peroxide and 0.03 parts of dicetyl peroxydicarbonate are placed in a 100 liter pressure vessel with impeller stirrer and baffle. After purging with nitrogen, 100 parts of VC are metered in and stirred at 110 rpm for 30 minutes. Subsequently, the mixture is fed to a Manton-Gaulin homogenizer and driven through pressure stages of 1.5 or 0.3 MPa in a polymerization with Kreuzbalrichrührer, polymerized at 52 ⁰ C with a gel phase temperature increase to 70 ° C and after 10 hours the remaining monomers relaxed. The latex is worked through spray drying at 55 ⁰ C foot temperature. The product is characterized by the following characteristics:

M _W : M "2.8

Particle size distribution from 60 to 2200 nm

Paste PVC: DOP = 3: 2 with a viscosity at D = 48.6 s " ¹ of 3300 mPas